Currently, a touch panel, particularly a capacitive touch panel (CTP), has become a main-stream configuration for a mobile display terminal. In order to reduce a cell thickness, the CTP is usually formed by combining an In-Cell touch panel and a liquid crystal panel in two ways, including Full In Cell and Hybrid In Cell. These two ways both involve problems in driving a touch scanning signal and a display driving signal in a time-division manner.
Taking Hybrid In Cell as an example, the time-division driving method includes scanning the signals within a time period of one frame in such an alternate manner as “display stage-touch scanning stage-display stage-touch scanning stage”. At the touch scanning stage, the display driving is paused and a pull up (PU) point of the paused-level shift register unit is always at a high level. Because elements of the shift register unit connected to the PU point have an inherent leakage current Ioff, an electric leakage will occur at the PU point via these elements. Hence, it is impossible for the PU point to be maintained at a high level (there will be a slow voltage drop within a certain period of time), and when the display is restored, the voltage will be less than voltages of the PU points at the other levels. As a result, a signal voltage outputted by a gate driver circuit at this level will be less than those at the other levels, and a dark line will occur when displaying. During the entire touch display procedure, there are several periods of time where the display stages and the touch scanning stages are paused alternately, so finally there will be several dark lines on the panel, which thus results in deterioration in the display effect, and even a display fault.